package handlers

import (
	"html/template"
	"net/http"
	"os"
	"path/filepath"
)

type TemplateRenderer struct {
	funcs     template.FuncMap
	templates map[string]*template.Template
}

func NewTemplateRenderer(templateDir string) *TemplateRenderer {
	funcs := template.FuncMap{
		"formatBool": func(b bool) string {
			if b {
				return "Yes"
			}
			return "No"
		},
		"formatStatus": func(s string) string {
			switch s {
			case "running":
				return "Running"
			case "stopped":
				return "Stopped"
			case "starting":
				return "Starting"
			case "stopping":
				return "Stopping"
			case "error":
				return "Error"
			default:
				return s
			}
		},
	}

	tr := &TemplateRenderer{funcs: funcs}
	tr.templates = make(map[string]*template.Template)

	pages := []string{
		"index", "login", "signup", "dashboard",
		"change_password", "admin_dashboard", "admin_users",
	}

	layoutContent, err := os.ReadFile(filepath.Join(templateDir, "layout.html"))
	if err != nil {
		panic(err)
	}

	for _, page := range pages {
		pageContent, err := os.ReadFile(filepath.Join(templateDir, page+".html"))
		if err != nil {
			panic(err)
		}

		// Combine: page defines "body", layout is the root template
		combined := string(pageContent) + "\n" + string(layoutContent)

		tmpl, err := template.New("").Funcs(funcs).Parse(combined)
		if err != nil {
			panic(err)
		}

		tr.templates[page] = tmpl
	}

	return tr
}

func (tr *TemplateRenderer) Render(w http.ResponseWriter, r *http.Request, name string, data map[string]interface{}) {
	tmpl, ok := tr.templates[name]
	if !ok {
		http.Error(w, "Template not found", http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := tmpl.Execute(w, data); err != nil {
		http.Error(w, "Template error: "+err.Error(), http.StatusInternalServerError)
	}
}